Method and apparatus for distilling oil shale



Feb 26, 1929- 1,703,413

c. 0. WHITE METHOD AND APPARATUS FOR DISTILLING OIL SHALE Filed Sept. 26 1927 2 Sheets-Sheet 1 1 ll 7 Z zn zl 1f I am Feb. 26, 1929 7 1,703,413

c. 0. WHITE METHOD AND APPARATUS FOR DTS'IILLING OIL SHALE Filed Sept. 26, 1927 2 Sheets-Sheet 2 Zjwowtoz attozmq Patented Feb. 26, 1929. v

UNITED STATES PATENTVOFFICE.

CLAYTON ORVILLE WHITE, 01 DE BEQUE, COLORADO.

METHOD AND API'ARATUS FOB DISTILLING OIL SHALE.

Application filed September 26, 1927. Serial No. 221,973.

' and other hydrocarbon products and oils and in anticipation of a probable depletion of the great stores of underground oil, experiments are constantly being carried on for the purpose of discovering the most practical way of treating oil shale for the purpose of obtaining oil and gasoline. These experiments have shown that this problem many difficulties that must be overcome before the production of oil from shale can be successfully carried out on a commercial basis.

Since the treatment of oil shale requires the application to the shale of high temperatures. it is obvious that the retorts in which the shale is heated must not have mechanisms having a number of relatively movable parts as it is impossible to properly lubricate bearings that are located inside of such retorts.

In my copending applications, Serial Numhers 152,889 and 203,640, filed respectively on December 0, 1926 and July 5, 1927, I have shown shale education retorts in which the shale moves through the heated zone by the action of gravity alone and which have wide flat bottoms that permit the ground shale to spread out into a thin flat layer in which the particles will roll and come into close contact with the heated metal surface of the bottom. In application Serial Number 152,- 889 my retort has been shown as of a length of about one hundred feet or over for the reason that the great speed at which the ground shale will travel will carry it through the heated zone too quickly unless the path is made quite long. In my application Serial Number 203,640, I have shown a retort that embodies some of the ideas of the retort shown and described in my other application, but which is formed from a plurality of angularly related sections that form a zigzag path and in which the velocity of the shale is reduced to practically zero at-the intersection of each section.

It is the object of this invention to produce a retort that shall combine the desirable features of the two retorts which have been shown and described in my prior applications and which, briefly described, consists of an elongated retorthaving a wide flat bottom over which the ,ground shale will flow under the influence of gravity. At spaced intervals the retort is provided with means for reducing the velocity of the shale practically to zero so that the speed or velocity can be kept as low as desired, thereby,

increasing the time that it will take for the shale to pass through a retort of a given length.

My invention can be best described and will be most readily understood when reference is had to the accompanying dra in which the invention has been illustrated and in which:

Fig. l vis a longitudinal vertical section through a retort constructed in accordance with the preferred form of my invention; FFig. 2 is a section taken on line 2-2,

ig. 1; I

Fig. 3 is a longitudinal section of a portion of my-improved retort shown in perspective to a somewhat enlarged scale;

Fig. 4 is a section through one of the velocity retarding devices;

Fig. 5 is a vertical section through a retort embodying another form of my invention; I

Fig. 6 is a longitudinal section through a secsion of the retort illustrated in Fig. 5; an

Fig. 7 is a section taken on line 7-7, Fig. 6.

In Fig. 1 of the drawing I have shown what I consider to be the preferred embodiment of my invention. In this embodiment the retort is built on the side of a hill and has a downward inclination of substantially f0rty-five degrees. Reference numeral 1 des ignates the inclined surface and 2 designates the masonry or brickwork which constitutes the furnace chamber of my retort. This furnace chamber is supported on concrete foundations 3, which are set into the ground in such a way that the parts will be firmly anchored so that there will be no danger of having the structure slide downwardly. The upper end ofthe furnace chamber terminates in a smokestack or chimney 4 which may be of any heighth desired. At the lower end of the furnace I have provided a recess 5 within which is located one or more gas burners 6 that serve to produce the heat necessary for the treatment of the shale. It is of course evident that as many burners may be provided as are found to be necessary for the purpose of producing the necessary amount of heat.

In order to employ my apparatus it is necessary to reduce the ore to a powder or to small particles and this is accomplished by means of a grinder or crusher which has been indicated by reference numeral 7 This crusher is connected by means of a chute 8 with a storage bin 9 which is provided with an inclined bottom 10. A hollow tube or conduit 11 communicates with the interior of the bin 9 and extends to the control valve 12. The delivery side of the controlvalve opens into the upper end of the retort 13. The construction of the retort constitutes the gist of this invention and has been illustrated quite clearly in Figs. 3 and 4, from which it will be seen that the retort consists of a plurality of sections which have been indicated by A. These sections each consists of a conduit formed from steel plates and which has a flat bottom 14 and also may have a flat top 15. The bottom and top plates are connected by means of narrow sides 16. The width and thickness of this conduit can be varied to suit the different conditions, but as an example it will be considered that plates 14 and'15 are twentyfour inches wide and that the sides 16 are three inches wide, the conduit will therefore have the shape of a rectangle like that shown in Fig. 2. The bottomlplate of each section terminates in a short piece 17 that is bent at right angles to the plane of the bottom and whose lower end is integral with or welded to the upper end of the bottom plate of the next lower section. Part 17 has a width substantially equal to the thickness of the conduit so that the top plates 15 of the next lower section will lie in the plane of the bottom 14 of the section directly above. The top plate of each section extends downwardly some distance below the part 17 where it terminates in a downwardly extending wall 18 that is connected with the upper end of the top plate 15 along line 19. This connection may be formed by welding or in any other suitable way so as to make a strong gastight joint. The stop plate 20 is secured to the under side of plate 15 a short distance below the wall 17 and extends to within a short distance of the bottom plate 14 of the next lower section so as to leave a narrow slot or opening 21 through which the ground shale may pass in the manner indicated in Fig. 4. A gas takeoff conduit such as that indicated by reference numeral 22 projects to the side of the'retort directly below the stop plates 20. The retort can be made as long as desired and the length of each section can be adapted to fit the requirements of the practical installation.

I ln Fig. 1 I have shown my retort as supported on a plurality of spaced channel irons 23 that arev located underneath the bottom of each section directly above the wall 17. The lower end of the lowermost section terminates ina valve 24 which has a hollow cylindrical member that can be rotated so as to remove the spent shale withp out opening the lower end of the retort to the admission of air. This valve may be operated periodically or it may be operated continuously by means of a motor. The

as takeoffs 22 extend to a condenser 97 that 1s located adjacent the furnace chamber and serves to condense the gas that has been liberated from the shale. The operation of this retort is as follows: The oil shale is first ground to a powder or so that the particles are quite small and will flow freely.

Gas is introduced through suitable pipesand mixed with air and this mixture is burned in the burner 6, thereby producing an intense heat which travels upwardly through the furnace chamber and heats the bottom of the retort sections to a very high temperature. When the valve 12 is open powdered shale will flow downwardly over the upper surface of the bottom plates 14, and, owing to the fact that these plates are flat the shale will spread into a thin layer which covers the entire width of the botexpense of its construction." In the retort which I have shown in Figs. 1 to 4 and which has just been described, the powdered shale which has been designated by reference numeral'28 in Fig. 4 flows downwardly over the bottom plates 14in a thin layer which permits the particles to roll and to move about in such a way that every particle comes into contact with the metal surface and becomes. thoroughly heated. When this shale powder reaches. theangle between parts 17 and 14, it will have attaineda considerable velocity and will flow across the space between the Wall 17 and the stop plate 20 and strike the latter so as to come practically to a stop.. The powder will then flow along the side of the stop plates 20 and on to the bottom 14 of the section directly beneath and will continue its flow until it reaches the next stop plates at the juncture of the other two sections. It is apparent that by this means the velocity of this shale powder is decreased and practically reduced to zero at the beginning of 05 tom as the shale particles are acted upon each section and therefore the powder will only attain such a velocity as can be reached while it flows along the bottom plate of one section. By making the sections veryshort, it is apparent that the velocity can be kept down to a very modest value, while if a greater velocity is desired, the length of the sections can be increased.

From the above it will be apparent that a retort constructed in the manner described may have a total length as great as may be found desirable and at the same time the velocity of the powder can be maintained very low and in this manner it is possible to obtain a more thorough and complete heating of thepowder' particles than with a retortwhose bottom surface lies in one plane' from one end of the retort to the other. This construction permits the retort to be made much shorter than would otherwise be possible and still obtain the most complete elimination of the hydrocarbons.

from the shale.

In Figs. 5 6 and 7 I haveillustrated another embodiment of my invention. The retort shown in these f gures is substantially the same as that described and shown in my copending application, Serial No. 203,640

and differs from that illustrated in Figs. 1'

to 4 mainly in this, that it is designed for use in a device'having a vertical zigzag furnace V chamber, whereas, theone shown in the other figures is intended to be used with an incline furnace chamber like that shown in Fig. 1.

In Fig. 5 reference numeral 29 represents the brick .or masonry work of the furnace.

This furnace has a zigzag chamber consisting of sections C and D which terminate in a Smokestack 30. The retort is formed of a plurality of sections 31 and 32 which are all constructed in the same. mannerand which have flat bottoms 33 and flat tops 34 connected by narrow side members 35. In the drawing the diiferent sections make an angle of ninety degrees with each other and the tops 34=of the different sections connect with the upper endsof the bottoms 33 of the sections directly beneath. The bottoms 33 of each section project be yond the plane of the sides 34 of the section below and terminate a short distance from the upper surface of the bottoms 33 so as to leave a narrow opening 36 through which communication is had between't heinterior of adjacent sections. Gas t'akeofi's 37 are secured to the tops 34 directly below the bottoms of the sections, and these takeofi's extend to and communicate with the interior of the condenser 38. .Pow'de'red shale is placed in the hopper 39 and admitted to the upper section of the retort by means of a valve 40. This. shale spreads over the,

upper surface of the bottoms 33'and flows downwardly under the influenceof gravity.

As the powdered shale reaches the end of v the bottoms 33, it, strikes the upper end of a the bottom 33 of the section directly beneath and has its velocity reduced practically to zero. As itpasses through the opening 36 its velocity is gradually increased by the action of gravity and is reduced again when it strikes the bottom of the next succeeding section. It will be seen from this description that regardlessof the total length of the retort, the velocity that can be. attained by the powdered shale is limited to that which is reached duringthe flow over the surface of anyone section, as the velocity is reduced practically to zero when it strikes the bottom of the section .below. In this manner it is therefore possible to keep'thev shale in the heated zone for a'much longer time than if this reduction of velocity at spaced intervals did not take place. i

In the construction here shown and described the shale passes in a practically solid stream across the opening between wall 17 and the stop plates 20 andjdoes not have any showering effect at this point. As it leaves the edge of plates 20, it is deposited on thebottom 14- in a layer whose thickness is substantially equal to the width of the gap 21 so that in effect there is a steady flow of shale across and through these two gaps. In the embodiment shown inFigs.

with the gas and this powder will flow through the pipes 37 into the condenser where it will be mixed with the condensate. By means of my construction the production of a' loose powder is prevented and thereby a clear-product obtained.

I also want to call. attentionto the fact 1 that with my. construction of retort the shale is constantly moving and therefore there is the retort.

Another advantage to which I have previously called attention is that the shale is -moved through the retort without the use of any mechanism and therefore there is no danger of breakage and no objectionable Wear such as would be the case if some mechanical means were provided for moving the shale.

By spreading the shale thinly over flat surfaces and permitting it to move downwardly by the action of gravity, all the no opportunity for it to cake and to clog I i shale is agitated sothat all the particles will have an opportunity to come into contact with the heated bottom surface and to be raised to thenecessary temperature. I

consider that the agitation of the shale by its downward flow is of great importance as the several particles thereby come into .intimate contact and have their temperatures raised to the degree necessary for complete elimination of the hydrocarbons.

Where the shale particles do not come into contact with the heated surface, the heat does not seem to penetrate them as readily as it does when actual contact is made. The reason for this is perhaps that heat is more readily conducted by conduetion and therefore the flow of heat is much faster than when the shale is in contact with the heated metal than if the particles were merely suspended in an atmosphere raised to the same temperature.

Having described my invention what I claim as new is:

1. In an oil shale. retort the combination of a plurality of interconnected hollow sections, each having a flat bottom, the bottom surfaces of said sections lying in different planes and being inclined at an angle greater than the angle of repose for powdered oil shale whereby oil shale will" flow by the action of gravity alone, and means located at the juncture of each of the sections for abruptly changing the direction of flow of the shale whereby the velocity is reduced.

2. An oil shale retort comprising a plurality of interconnected enclosed metal sections forming a conduit, each section having a flat bottom, the bottoms of the several sections lying each in a separate plane, the plane of each bottom section being inclined to the horizontal. at an angle that is slightly greater than the angle of repose for powdered shale whereby the latter will flow by the influence of gravity alone from the top to the bottom of the retort, means located at, the junction of adjacent sections for abruptly changing the direction of flow and thereby reducing the velocity of the powdered shale as it passes from a higher to a lower section, and gas takeoiis for removing the volatile products.

3. An oil shale retort comprising a gastight metal conduit composed of a plurality of nonaligned sections, each section having a flat wide bottom inclined to the horizon at such an angle that powdered shale will flow over the upper surface thereof by the action of gravity alone, a stop plate extending downwardly across the plane of the bottom of each section directly beneath the lower end of the bottom whereby the powdered shale will strike the stop plate and have its v locity greatly reduced as it passes from an upper to a lower. section, a gas takeoff conduit located below each stop plate, and means for heating the retort.

4. In an oil shale retort the combination of a pluralit of interconnected, nonaligned tubular sections having flat bottoms that moans lie in spaced, substantially parallel planes,

said retort being formed from metal, the

transverse section of the retort forming a closed area, the bottoms of the sections being inclined to the horizontal at an angle greater than the angle of repose for powdered shale whereby the latter will flow by the action of gravity alone, the top of each section extending downwardly a greater distance than the bottom, a batiie plate secured to the top of each section and extending transversely of the plane of the bottom, but spaced from the lower end of the latter. the lower edge of the battle terminating a short distance from the bottom of the next lower section and a gas takeoff adjacent ach battle.

5. In an oil shale retort the combination of a chamber closed at the top and inclined to cause the shale to travel downwardly therethrough by gravity alone, the bottom of the chamber being stepped downwardly at intervals, and battles respectively located below and spaced from'butadjacent to the step oti'sets oi the bottom of the chamber, the-said battles being in the path of the shale and retarding the normal speed due to gravity acceleration, whereby the period of travel of the shale through the chamber is increased and the length of the retort re quired in order to properly heat the shale, correspondingly diminishe h 6. An oil shale retort comprising a chamber closed at the top and inclined to cause the shale to travel downwardly therethrough bygravity alone, the bottom of the chamber being stepped downwardly abruptly at intervals, and baffles respectively located below and spaced from but adjacent to the step offsets of the bottom of the chamber, the said battles being in the path of the shale and retarding the normal speed due to gravity acceleration, whereby the period of travel of the shale through the chamber is in creased and the length of the retort required in order to properly heat the shale, correspondingly diminished, means for heating the chamber and a gas takeoff communicating with the chamber adjacent to each battle.

7. The method of distilling oil shale which consists in reducing the shale to small particles and passing the said reduced productin a thin layer of substantially uniform thickness through a heated chamber in a direction inclined to cause the shale to travel by gravity alone, the stream of shale being stepped downwardly at intervals and bafiled a short distance below each of said step movements, to check the speed due to gravity acceleration, but without stopping its travel, and removing the volatile products.

8. The method of distilling oil shale which consists in reducing the shale to a finely divided condition, passing this product in a thin layer of substantially uniform speed clue to gravity acceleration, but without stopping its travel, and drawing off the Volatile products from the chamber at suit- 10 ably spaced intervals.

In testimony whereof I atlix my signature.

CLAYTON ORVILLE WHITE. 

